Note that this definition does not depend on the choice of the partition
\(D=\lbrace t_k\rbrace _{k=0}^p\)  of \([a,b]\)  and on the choice of the numbers \(\varepsilon _k\) , as long as
they satisfy the above properties, see e.g. [1]}. This property
will also follow from our main result below (see
Theorem REF  and Remark REF ).
